Delphinidin: A Novel Agent For Treatment Of Psoriasis

描述（申请人提供）：牛皮癣的特征是角质细胞增生，颗粒层丢失和角化不全分化。caspase -14是一种非凋亡性caspase家族成员，其在表皮中的表达仅限于基上层，并与终末分化有关。在正常皮肤中，caspase-14在整个基底上层的细胞质和细胞核中检测到。然而，在银屑病皮肤的角化不全区域，其特征是缺乏核破坏，caspase-14表达下调。上调caspase-14表达的策略可能对包括牛皮癣在内的角化不全疾病构成新的治疗贡献。导致表皮角质形成细胞分化的药物可能对银屑病有治疗作用，也可能对伤口愈合和其他增生性皮肤病有用。因此，确定一种自然发生的补充和替代医学方法，使用一种诱导表皮角质形成细胞分化而不诱导细胞凋亡的药物是一个非常理想的目标。飞燕草苷是色素类水果和蔬菜中的一种主要花青素，具有很强的抗氧化活性。最近，我们已经表明，局部应用飞飞草苷可以抑制紫外线b介导的SKH-1无毛小鼠皮肤DNA损伤和tunel阳性细胞的形成。然而，目前还没有研究考察飞燕草苷治疗对正常人角质形成细胞功能的影响。我们的初步未发表的研究值得注意，我们已经证明了飞鸽苷诱导正常人表皮角质形成细胞中procaspase-14蛋白和mRNA的表达。我们还发现天花素和转谷氨酰胺酶-1的蛋白和mRNA表达显著增加。值得注意的是，在相同的处理条件下，飞燕草苷没有诱导细胞凋亡。这种显著的区别构成了本应用程序的基础，该应用程序旨在研究飞燕草苷在体外人类重建皮肤模型系统和临床前体内环境中对角质细胞分化的影响。本应用需要验证的中心假设是“delphinidin会通过诱导caspase-14和其他早期和晚期分化标志物的表达以及抑制细胞增殖而不诱导凋亡来减少牛皮癣样病变的病理标志物”。为了验证我们的假设，提出了以下具体目标：(1)作为表皮完全分化的实验模型系统，探讨飞飞蓟苷处理是否增加了体外三维人重建皮肤中角质细胞分化标志物的分布和表达水平；(2)采用片状皮肤（fsn/fsn）小鼠和片状皮肤（fsn/fsn） caspase 14-/-小鼠，研究在体内情况下外用飞飞蓟苷对牛皮癣样病变病理标志物的影响。研究将确定caspase- 14的表达是否与表皮病理症状的减轻有关。

DESCRIPTION (provided by applicant): Psoriasis is characterized by keratinocyte hyperproliferation, loss of granular layer and parakeratotic differentiation. Caspase-14 is a nonapoptotic caspase family member whose expression in the epidermis is confined to the suprabasal layers, and is associated with terminal differentiation. In normal skin, caspase-14 is detected in the cytoplasm and nuclei throughout the suprabasal layers. However, in the parakeratotic regions of psoriatic skin, which are characterized by the lack of nuclear destruction, caspase-14 expression is down-regulated. Strategies to upregulate caspase-14 expression may constitute a novel therapeutic contribution to diseases involving parakeratosis, including psoriasis. Agents that lead to differentiation of epidermal keratinocytes may have therapeutic effects against psoriasis and could also be useful in wound healing and other hyperproliferative skin disorders. Thus, identifying a naturally occurring Complimentary and Alternative Medicine approach with a agent that induces differentiation of epidermal keratinocytes without inducing apoptosis is a highly desirable goal. Delphinidin, a major anthocyanidin in pigmented fruits and vegetables, possesses potent antioxidant activity. Recently, we have shown that topical application of delphinidin inhibited ultraviolet B-mediated formation of DNA damage and TUNEL-positive cells in SKH-1 hairless mouse skin. However, no studies have examined the impact ofdelphinidin treatment on the function of normal human keratinocytes. Our preliminary unpublished studies are noteworthy where we have demonstrated that delphinidin induces procaspase-14 protein and mRNA expression in normal human epidermal keratinocytes. We also found a significant increase in the protein and mRNA expression of involucrin and transglutaminase-1. It is noteworthy that delphinidin under identical treatment conditions did not result in induction of apoptosis. This remarkable distinction forms the basis of this application which is designed to investigate the effect of delphinidin on keratinocyte differentiation both in in vitro human reconstituted skin model system and in preclinical in vivo settings. The central hypothesis to be tested in this application is that "delphinidin will reduce the pathological markers of psoriasiform lesions by inducing the expression of caspase-14, and other markers of early and late differentiation and by suppressing cell proliferation without inducing apoptosis". To test our hypothesis, the following specific aims are proposed: (1) To investigate whether delphinidin treatment increases the distribution and expression level of keratinocyte differentiation markers in in vitro three- dimensional human reconstituted skin as an experimental model system that allow complete epidermal differentiation, and (2) To examine the effect of topical application of delphinidin on pathological markers of psoriasiform lesions under in vivo situation employing flaky skin (fsn/fsn) mice and flaky skin (fsn/fsn) caspase 14-/- mice. Studies will be conducted to determine whether caspase- 14 expression is associated with reduced symptoms of epidermal pathology. PUBLIC HEALTH RELEVANCE: This application intends to define a novel agent delphinidin present in pigmented fruits and vegetables for the treatment of psoriasis and could also be useful in wound healing and other hyperproliferative skin disorders.